All are equivalent except x< -2, x-2< 4, 2x< -4, x-2< -4 ?

To figure out which is not equivalent to the others,, we must solve each option provided. x < -2 is already solved,, so there is no need to do any work that option.
The first step for solving x - 2 < 4 is to move the constant to the right side and then change its sign.
x < 4 + 2
Now add the numbers together to get your final answer.
x < 6
This means that we have one option that equals x < -2 and one option that equals x < 6.
Let's now solve 2x < -4 to see what that one equals. In order to solve this,, we need to divide both sides of the inequality by 2.
x < -2
Now we can see that it looks like all of the expressions are equivalent except for x - 2 < 4. Before we can confirm this though,, let's solve for x - 2 < -4. The first step for solving this is to move the constant to the right side and change its sign.
x < -4 + 2
Now calculate the sum of these two numbers to get your final answer.
x < -2
This tells us that all of the options are equivalent except for x - 2 < 4,, or option B.
Let me know if you have any further questions.
:)